In Acorus both upper and lower epidermis cells are rectangle or rhombus, and the stomata apparatus are paracytic and arrange in rows along the veins.

菖蒲属叶上下表皮特征基本一致，细胞形状为长方形或近菱形，气孔器平列型，成纵行与叶脉平行排列；

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They found a metal-like shine on the leaves, indicating that the upper and lower epidermis were dying.

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